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Importance of porins for biocide efficacy against Mycobacterium smegmatis

Elrike Frenzel1, Stefan Schmidt, Michael Niederweis

  • 1Schülke & Mayr GmbH, Research & Development, 22851 Norderstedt, Germany.

Applied and Environmental Microbiology
|March 15, 2011
PubMed

Insights

Mycobacterium outer membrane porins significantly enhance resistance to various biocides. Deleting these porins increases resistance to disinfectants, crucial for understanding mycobacterial survival strategies.

Area of Science:

  • Microbiology
  • Biochemistry

Background:

  • Mycobacteria exhibit exceptional resistance to biocides due to their unique outer membrane barrier.
  • Porins, channel-forming proteins in the mycobacterial outer membrane, are implicated in biocide susceptibility.

Purpose of the Study:

  • To investigate the role of Msp porins in the biocide resistance of Mycobacterium smegmatis.
  • To determine how porin deletion affects susceptibility to a range of biocidal agents.

Main Methods:

  • Utilized the alamarBlue assay to quantify biocide resistance in isogenic Mycobacterium smegmatis mutants.
  • Employed quantitative suspension tests (EN 14348) to assess disinfectant efficacy against porin mutants.

Main Results:

  • Deletion of Msp porins increased Mycobacterium smegmatis resistance to isothiazolinones, formaldehyde-releasers, and lipophilic biocides by 2- to 16-fold.
  • A porin triple mutant showed an 8-fold decreased susceptibility to a complex disinfectant, with 100-fold improved survival in suspension tests.

Conclusions:

  • Porins play a critical role in determining the susceptibility of Mycobacterium smegmatis to biocides.
  • Targeting porins could be a strategy to enhance the efficacy of disinfectants against mycobacteria.

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